1. Field of Invention
The present invention relates to a water treatment system, and more particularly to a water treatment system for a water animal feeding facility wherein the water treatment system is adapted to efficiently and effectively discharge aquatic waste, facilitate air exchange of water, and filter unwanted substances contained in the water for recycling use.
2. Description of Related Arts
A conventional water animal feed facility for commercial purposes typically comprises a feeding pond containing a predetermined amount of water, an air supply device provided in the feeding pond to mix the water with air so as to provide enough oxygen to the water animal which is being fed in the feeding pond, and a water filter arrangement communicating with the feeding pond to filter aquatic waste in the water so as to keep the water in the feeding pond clean. In order to nurture, for examples, fishes in the feeding pond for commercial purposes, the water, the air supply device and the water filter arrangement must be of high quality so as to create the best aquatic environment in the feeding pond.
However, there exist several problems for this kind of conventional water animal feeding facility. First, the water filter arrangement tends to be ineffective and inefficient. As a matter of fact, the feeding pond usually has a plurality of water outlets spacedly formed at the sidewalls thereof wherein water is pumped through the water outlets for extensive filtering. The filtered water is then pumped back into the feeding pond for recycling use. A major problem for this water filter arrangement is that the rate of filtering of water with respect to every point of the feeding pond is non-uniform so that there exist some portions, particularly the corner portions, of the feeding pond the water contained therein cannot be filtered effectively. As a result, the water contained in the feeding pond cannot be filtered uniformly so as to affect the filter performance of the water filtering system as a whole. Aquatic waste tends to remain at the corner portions of the feeding pond so as to adversely affect the health of the fishes at those portions. One way of remedying this problem is to increase the pumping power of the water filter arrangement so as to create turbulence within the feeding pond for drawing larger amount of water at a specified unit of time. However, this inevitably increases the energy consumption of the water filter arrangement and therefore increases the cost for feeding the fishes.
Secondly, there exits a common phenomenon that for a typical feeding pond, the fishes tend to stay at a position near the water surface. This may be explained by the fishes' desire to obtain more oxygen and food which are normally concentrated near the water surface. As a result, those staying at the bottom part of the feeding pond would have less nutrients as well as oxygen supply. Therefore, they may not growth at a satisfactory rate or have health problems. Moreover, if a substantial number of fishes stay at the upper portion of the feeding pond, other parts of the feeding pond is essentially wasted because they simply cannot nurture fishes of satisfactory quality.
Thirdly, since all of the fishes fed in the feeding pond are the subject of business transactions, users tend to put as many fishes as possible in a particular feeding pond so as to generate more sales and minimize waste of resources. As a result, most feeding ponds are extremely packed with fishes so that they don't have much space to move in the water. The long term consequence of this is that the fishes do not have enough exercise to build up their muscles and strength. This may be commercially undesirable because consumers usually prefer stronger fishes for better muscle texture, and more importantly, better taste.
Fourthly, the air supply device usually comprises a pump for injecting air bubbles into the water so as to mix the air with the water. This requires a considerable amount of energy. Moreover, it is difficult to guide the air bubbles to distribute evenly within the feeding pond and, as a result, some fishes may not get enough oxygen even for survival. In the long term, the death rate of the fishes will increase and for those surviving fishes, their health may not be in good condition.
Fifthly, it is well known in the art that aquatic waste, such as fish's feces, would produce unwanted chemicals, such as ammonia, which cause harmful effect to the fishes in the pond. As a result, conventional filtering systems are devoted to filter these aquatic wastes. However, conventional filtering systems usually draw water from the pond and guide it to flow into several filter layers for blocking the unwanted aquatic waste. Filtered water is then driven to flow back to the pond for recycling use. As a result, if the filtering systems have poor effectiveness or efficiency, the unwanted chemicals would accumulate in the pond so as to adversely affect the health of the fishes. As a matter of fact, if the ammonia concentration in the fish pond is larger than 4 ppm, the fishes may die as a result.